The present invention relates to a golf club head having a hollow structure and made of a metal and a manufacturing method for the same, more particularly to a wood type or similar type golf club head and a manufacturing method for the same.
As the wood type golf club head represented by a driver and a fairway wood, the club heads having a hollow structure and made of a metal have been widely used. Generally, the wood type golf club head having the hollow structure includes a face part for hitting a ball, a crown part constituting an upper face part of the golf club head, a sole part constituting a bottom face part of the golf club head, a side part constituting side face parts on a toe side, a back side and a heel side of the golf club head, and a hosel part. A shaft is inserted into the hosel part of this golf club head and is fixed thereto with adhesive or the like. Recently, a variety of golf head clubs called “utility clubs” have been marketed, and as a kind of such a utility golf club head, a variety of golf club heads resembling the aforementioned wood type golf club head (i.e., golf club head including the face part, the sole part, the side part, the crown part and the hosel part) have also been marketed.
Although as a metal for forming this hollow golf club head, aluminum alloy, stainless and titanium alloy are used, in particular, titanium alloy has been widely used in recent years. As for a method for manufacturing the metallic hollow golf club head, Japanese Unexamined Patent Application Publication No. H6-327796 discloses in paragraph of its specification a method in which a face member is welded on a head main body having a sole part and a side part, and next, a hosel member is welded thereto, and, a crown member is welded thereto, followed by a finishing work.
To increase a flying distance of the metallic hollow golf club head, a variety of golf club heads capable of hitting a ball over a long distance by raising the coefficient of restitution of the ball due to deflection of the face surface (generally called the “trampoline effect”) were marketed. However, the official golf rules have been revised to restrict excessive fly of the ball, and consequently, the coefficient of restitution has been restricted. Furthermore, the volume of the golf club head has been limited to 460 cc or less.